Efficient guidance systems for airborne munitions and efficient control systems for aircraft have always been in high demand. The main objectives for new technologies in aerospace have always been increased speed and range in aerovehicles and reduced volume and weight of vehicle components. In recent years, smart structures have been introduced to replace traditional control actuation systems while interest in active flow control technologies have developed. For smart structures to be effect in active flow control depends on a micro-flow effector's ability to influence the macroscopic flow around the aircraft body. One approach which contributes to this control is the use of flow control surfaces deployed at various points on the aircraft superstructure. For airborne munitions, such control surfaces can be deployed in the forebody of the munition as missiles with slender forebodies face significant yawing moments under asymmetric vortices. Controlling forebody vortex asymmetry is dependent on the sensitivity of the asymmetric flow to the distance between the micro-flow effector and the nose top. The closer the micro-flow effector is to the nose tip, the lower the power required to trigger flow changes.
As such, flow control using micro-surfaces can be applied where manipulation of the velocity and pressure field is desired. Micro-flow effectors can be used in place of traditional control surfaces to reduce weight and volume while maintaining control authority. Boundary layer separation on aircraft wings needs to be controlled because it can result in reduction of lift and micro-flow effectors can be used for separation control.
Current state-of-the-art actuators are based on electromechanical devices and are often used in conventional missile control actuation systems. Examples of such actuators may be found in U.S. Pat. No. 6,685,143 issued to Prince et al, and U.S. Pat. No. 7,070,144 issued to DiCocco et al., the contents of both are being incorporated herein by reference. However due to the nature of flow effectors, the control surface must be close to the nose tip where volume is highly constrained. Since electromechanical systems, such as those disclosed by Prince and DiCocco, require electric motors to be connected to control surfaces through gear trains, the volume used by the components exceed the volume available in the nose envelope. There is therefore a need for a compact actuation system that mitigates if not overcomes the shortcomings of the prior art.